First open the JDDD interface to the laser synchronization
Either type ./jddd into a console at the ~erpopr home directory
Or, press the jddd button on the main EDM window
Eventually... a window like this will pop up
Press the "50 MHz Synchron." button and a new window will pop up
The default is unfortunately to point at the wrong hardware, so please select "UTCA02_DAMC1" from the upper-right dropdown menu.
Now, there should be visible data as below
Determine current state of synchronization
Example "Turned on and working" state
All of the upper-left buttons are green
The timing jitter is something around 300-400 fs (not >600 fs, not <100 fs, and not jumping around by factors of 2)
If the timing jitter looks suspicious, the laser oscillator probably needs adjustment (requires laser training)
Example "Turned off, but still working" state
Things to check
Upper left buttons are grey, and the state is redand says "RF lock is open"
The error frequency is ~0-50 KHz, and drifting only slowly, no jumps on the 100-1000s of KHz scale
If there are big jumps, the laser oscillator probably needs adjustment (requires laser training)
To begin synchronization
Click "close RF lock"
Click "FPGA FB loop enable"
Watch as the error frequency (eventually) goes to zero, though it may briefly increase at first
When it goes to zero, things should turn green, and the piezo voltage will slowly increase to the happy range (currently ~60-90V)
Example "Turned off, and laser is not working" state
(NEED example picture)
If the data looks like it is just very low amplitude noise, then the laser oscillator is probably turned off
The timing jitter will usually report a very good number in this state, ~10s of fs, and this is an erroneous reading
Turning on the oscillator requires laser training
If the data has a large amplitude, but the "error frequency" is jumping around, then the settings of the laser oscillator probably need adjusting, and this also requires laser training.